About the Water Pump-Whale Water System

Pump-Whale and Pressurised Water Systems

The primary purpose of the water pump is to supply and pressurise the water system from the water tank. The se lection of the pump is based on the number of water outlets to be supplied and the flow rate required. If the water pump-Whale is not rated correctly for the system then the water flow will decrease when another outlet is opened. Not unlike at home sometimes although it is more noticeable on a boat

The Diaphragm Pump

This is the most common pump unit and they are robust and also are designed for multi-outlet systems. I use a pump-Whale, Gulper 220 on my own boat. They are very tolerant to dry running conditions, are self-priming, are relatively quiet in operation and have inbuilt hydraulic pulsation dampening.

The Impeller Pump.

These pumps normally have a pump with bronze casing and nitrile or neoprene impeller. They are less tolerant to running dry and they are self-priming and are not generally used.

VSD Pumps

Some pump makers have tried to overcome pulsation problems with pumps like the Sensor-Max VSD (Variable Speed Drive) water pump from Jabsco. This pump unit has a Hall Effect pressure sensor for the water flow and varies the motor speed to maintain constant pressure. This does away with the requirement for an accumulator and pressure switches. The VSD controls the motor speed using a PWM DC motor controller.

About Pump Wiring

There a couple of key installation points that need to be followed when installing pump-Whale or any other pumps.

Cable Sizes Ensure that the cable is rated for maximum current draw and voltage drop. Voltage drop problems are very common, and over sizing the cable is a good practice.

Connections Connections directly on to pumps is common, and ensure the crimps are done properly. Also put some Vaseline over the connection to stop moisture getting to the connection lugs. Where wire tails require a butt splice, ensure that they are crimped properly. Some pumps with integral pressure switches require connection directly to one side so ensure this is properly done.

The Water System Strainer

The strainer is installed in the water suction line to the pump. The primary purpose is to protect the pump from damaging sediment and particles from the storage tank. It is essential that the stainless steel element is regularly cleaned, and blockages are most frequent at new vessel commissioning, or after refilling an empty tank. I have seen a number of boats where the element has been removed because the owners were tired of cleaning blockages. The result will be early pump failure. It is good practice to clean the system and eliminate the cause. After cleaning the element, ensure that a good seal is made with the transparent inspection cover, as this is a common cause of air being drawn into the system. Ensure that the seal is in good condition, and a smear of Vaseline or silicon grease often helps.

Water System Accumulators.

An accumulator is an essential part of any water system. The basic principle is that air will compress under pressure and the water will not. The accumulator is a tank filled with air that fills to approximately 50% with water when the pump operates. After the pump stops running, the compressed air provides pressurised water stored within the accumulator. It serves two functions, the first being a pressure buffer or cushion which absorbs fluctuations in pressure. The effect is to operate quietly, and the pump pressure switch is able to reach the cut-off pressure, which increases the life of the pump, motor and the pressure switch. The life of the pump is extended, as the accumulator will prevent the pump operating as soon as the water outlet is opened. If a large accumulator is installed, the pump will operate less, and where large demand systems are installed, larger accumulators are required.

Accumulators come in two main types. The non-pressurised types are typically plastic cylinders, which are installed upright within the system. These also have a cock at the top to vent off air within the water system. With tanks that do not have bladders to separate the air and water, the tank must be drained every few months, as the air gradually disappears and the tank no longer functions as an accumulator, there must be air inside. The pressurised accumulator types have an internal membrane or bladder that can be externally air pressurised with a bicycle pump, or are factory pre-pressurised with nitrogen. At installation the following procedure must be performed:

1. Turn pump off.

2. Open outlets and release system pressure.

3. Using a car tyre pressure gauge, release nitrogen until pressure falls to 5 psi below pump cut-in pressure.

4. If too much pressure is relieved, use a bicycle pump to increase to correct pressure.

Water Filters. Filters should be fitted to all drinking water outlets, and in most cases, this is the galley outlet. A filter will remove small particles, off tastes and smells caused by tank water purification chemicals, as well as some bacteria. This will form in pipes and tanks during extended periods of inactivity. You can sterilize the system, such as the tanks procedure and flush the system out. Always install a filter with easily replaceable filter elements and replace promptly at the nominated service life completion. Always cleanse the water system before installing a new filter. Filters are generally manufactured of activated carbon. Greater water quality can be had from filters that use porous ceramic, which removes all particles and detectable bacteria. A good filter should always provide a test report issued by an appropriate authority. It should be rated for the expected flow rate (in litres) and should be renewed at the due date. A filter is never a substitute for clean tanks.

Water System Piping

Piping should be of high quality food grade material. Ideally a pipe that is suited to both hot and cold water should be used . Piping should be of high quality food grade material. Ideally a pipe that is suited to both hot and cold water should be used. The following should be observed when selecting and installing piping. The piping should be non-toxic and suitable for potable water systems use and must not be able to support microbiological growth. Piping is of two types, the Semi-Rigid Piping and Whale has a color-coded semi-rigid pipe system. I prefer the pump-whale water web system. Ensure that pipe is not kinked, and where tight bends are required install a bend. The system is excellent and I used this on my own boat. You just need a special cutting tool. Many use flexible hose. Ensure that piping is of required standards and as it is very prone to kinking installation should be done with care. Piping must be capable of withstanding the water system pressures. Pump-Whale piping is rated at 60 psi and 90°C. When installing piping, the longer the run, the larger the pipe required. This reduces the friction losses.

Pipe fittings must be capable of withstanding pressures in the system. Nuisance leakage can be avoided. Where plastic hoses are used, generally PVC tee-joints are installed with clips. An excellent system is the pump-Whale system. These enable easy system installation and servicing. There are many different taps, valves and showerheads on the market. Always choose good quality items, and choose only those that are compatible with the whole plumbing system to enable easy spares sourcing. Reputable names include pump-Whale and Jabsco. If you are using a non-flexible and permanent showerhead, opt for one of the domestic low water consumption units. Ensure that all piping or hose connections are double clamped.

Choose Pump-Whale or Jabsco ot other, but choose quality

Pump-Whale or Jabsco, get your water system right!